Densifying mill



June 6, 1944. F. R. MURPHY ETAL 2,350,632

DENSIFYING MILL Filed March 10, 1942 s She'ts-Sheef 1 FRANCIS R MURPHY RAY H BEBOUT A oRNEYs I -Jun 6,1944. F. R. MURPHY HAL 2,350 632 DENSIFYING MILL Filed March I0, 1942 s Sheets-Sheet 2 FRANCIS R MU RPH\ RAY H BEBOUT INVENTORS A RNEYS June'6, 1944. F. R. MURPHY. EI'AL 2,350,632

DENSIFYING MILL Filed March 10, 1942 3 Sheets-Sheet 5 RAY H BEBOUT INVENTORS A oRNEYs FRANCIS R MURPHY Patented June 6, 1944 2,350,632 DENSIFYING Min.

Francis R. Murphy and Ray 11. Bebout, Toledo,

Ohio, assignors, by memo assignments, to 11bbey-Owens-Ford Glass Company, a corporation of Ohio Application March 10, 1942, Serial No. 434374 4 Claims.

This invention relates to apparatus for densifying, and more particularly to a machine for densifying or compacting fusible powdered materials such as molding compositions.

Molding compositions, whether thermoplastic or thermo-setting, may be supplied to users in various colors, and often have varying ingredients, such as diflerent plasticizers, to adapt the molding compositions for different types of moldform blisters, voids or other flaws in the molded article.

It is therefore customary to subject the finely powdered mixture to a densifying operation.

The powder may, for example, be placed in a kneading device in which it is warmed so that it becomes plastic and is kneaded to expel air I and other gases and form a homogeneous dense mass. After it has been thus kneaded, it is put through a grinder to reduce the mass to granular form.

The usual densiiying device must be charged with individual batches of powder and, of course. discharges the densified material in batches.

It isan object of this invention to provide a machine for densifying fusible powdered mate rial in a continuous operation. 1

It is a further object of this invention to provide a machine which will continuously densify fusible powdered material into a mass having characteristics which will permit subsequent granulation of such mass to be more easily accomplished.

More specific objects and advantages are apparent from the description, in which reference is had to the accompanying drawings illustrating a preferred form of densifying machine embodying the invention.

In the drawings:

matic sectional view, taken substantially on the line IV-IV of Fig. 11.

These specific drawings and the specific description that follows merely disclose and illustrate the invention, and are not intended to impose lnmtations upon the claims.

The main frame of the machine consists of two webbed members ill and II, each of which is mounted, by means of bolts II, on one of two parallel "I" beams i3 which are a portion of the main frame 01 the building in winch the machine is located. A stationary bearing block it is mounted on the upper surface of the webbed member Ill by means of bolts It. A similar stationary bearing block ii is similarly mounted on the webbed member it (see Fig. 111). The two bearing blocks l4 and ii are coaxially located and rotatably support a pressure roll II.

The pressure roll ll consists of a hollow cylindrically-shaped member list eachend of which there is fastened, by means of stud bolts IS, a hollow trunnion 20. The outer surface of each of the trunnions 20 carries a race 2! which supports the pressure roll ll on rollers 22 which bear on outer races 23 located in the bearing blocks l4 and".

Fig. I is a side elevational view of a densifying machine embodying the invention.

Fig. II is a plan view of the machine illustrated in Fig. I.

Fig. III is a fragmentary sectional view, taken substantially on the line III-III of Fig. II.

Fig. IV is a fragmentary somewhat diagram- A sliding bearing block 24 (Fig. I) is mounted on ways 25 on the. upper surface of the webbed member Ill for movement longitudinally on the member III. A similar sliding bearing block 26 (Fig. 11) is similarly mounted on the upper surface of the webbed member ii. 'I'hebearing blocks 24 and 26 rotatably support a pressure roll 21 which is identical in construction and method of mounting to the pressure roll II.

The rolls ii and 21 are 01 uniform diameter throughout their length except at the ends of the rolls where there are located annular shoulden 28 which project above the surfaces of the rolls only a few thousandths of an inch. Oneof two spacers 2! and 3D is bolted to the side-of each of the stationary bearing blocks and I6 and extends horizontally toward the side of the corresponding slidable' bearing block. The center lines of thespacers 28 and 30 are located on of the bearing blocks above the outer races 23.

and the rod 32 in that portion of the blocks below the outer races :1. Nuts II are threaded on the ends of the tie rods II and 32 extending outside the bearing block l4, and bear against that block. The Opposite ends of the tie rods II and 32 extend horizontally through a pressure block 34 'which is mounted securely on the upper surface of the webbed member ill by means of bolts 35. Nuts 36 are threaded on the ends of the tie rods 3| and 32 which extend beyond the pressure block 34.

A hydraulic cylinder 21 is provided in the pressure block 34 and its ram 18 is located concentrically with respect to the spacer 24. and with its center line on the same plane as the axes of the rolls l1 and 21. The end of the ram 28 is rounded and bears against a rounded projection 39 on the side of the movable bearing block 24.

Similar tie rods 40 and 4i (Fig. 111) are similarly mounted in the stationary bearing block it and movable bearing block 26, which are located on the webbed member II, and pass through a pressure block 42 (Fig. II) similar to the pressure block 34 and are similarly secured thereto. The pressure block 42 has a hydraulic cylinder, and a ram which bears upon a rounded projection on the bearing block 26 and these parts are identical with the parts already described with reference to the pressure block 34.

A four-way swivel-type pipe fitting 43 (Figs. 1 and III) has its rotating portion mounted in an end plate 44 (Fig. III) on each of the two trunnot necessary to drive the auxiliary rolls 54 and ll because friction between these rolls and the nions 20 which are mounted in the bearing blocks l4 and 24. The fittings 43 are held against rotation by means of brackets 45 which are secured to the fittings 43 and to the blocks l4 and 24.

An outlet pipe 46 is threaded into the stationary portion of each of the fittings 43 and is connected with an inner curved pipe 41 which extends upward to a point near the inner surface of the hollow roll 11 or 21. An inlet pipe 48 is also attached to the fitting 43 and connects to an outer pipe 4! surrounding the pipe 41 in'the interior of each of these two hollow trunnions 20.

By means of these pipes and fittings, a supply.

of heating fluid can be circulated through the rolls l1 and 21 to maintain the surface of these rolls at a high temperature. The trunnions supporting the opposite ends of the rolls, which are mounted in the bearing blocks 16 and 26, have attached to their outermost ends a pair of intermeshing bull gears 50 and II (Fig. 11) which are driven by means of a pinion 52 mounted on a drive shaft 53. which is iournaled in a bearin block 54 bolted to the end of the webbed member I I. A housing 55 covers the gears 54 and ii and the pinion 52.

An auxiliary leveling roll 56 (Fig. 11) is mounted in bearing blocks 51 and 54 which are secured to the upper surfaces of the bearing blocks 14 and I6 respectively. The auxiliary leveling roll 56 is fixedly positioned by the blocks I1 and 54 so that its periphery clears the periphery of the roll H by a substantial amount (Fig. I). An auxiliary pressure roll 54 is journaled in brackets and GI which are pivoted on the trunnions of the leveling roll 58 and which permit the pressure roll 59 and its brackets 44 and ii to swing about the axis of the leveling roll 66. The leveling roll 56 may be rotated, for example by means of a pinion 62 (Fig. 11) which is in mesh with the bull gear ill, and the pressure roll 5! may be rotated by means of a chain 42 engaging sprockets 64 and 65 secured to the trunnions of the rolls SI and I! respectively. In the case of some materials it is material will turn them. Cooling fluid is introduced into the interior of the rolls I6 and II through inlet pipes 68 (Fig. I) which are secured to swivel-type fittings 61 fastened to'thc ends of the hollow trunnions of the rolls 54 and I. The fluid is carried away from the rolls 54 and I! through outlet pipes 42 (Figs. 11 and III) which are attached through similar fittings to the opposite trunnions of the rolls. Thermostaticailycontrolled valves 68 are located in these outlet lines to control the egress of the cooling fluid and thus regulate the temperature of the rolls '6 and 52.

A similar fixed leveling roll 10 and rockable pressure roll'1i are similarly mounted on the bearing blocks 24 and 24 above the roll 21 and may be driven by a pinion 12 in mesh with the bull gear ii. The rolls 10 and 1| are cooled by means of fluid introduced through their hollow trunnions from inlet pipes 13 and carried therefrom by outlet pipes 14.

A pair of scraping knives 15 (Figs. I and IV) extend along the surfaces of the rolls l1 and 21 below the point of closest approach of the rolls for scraping off any material which may adhere to the surfaces of the rolls. .Each of the knives 15 is fixed on a rockable shaft 16 to which is secured an arm 11 which carries a weight 14 so located as 'to press the edge of the knife 16 against the surface of the roll. The shafts 16 are journaled on a cross frame 14 which extends.

across from the webbed member Ill to the webbed member ll. between the rolls I1 and 21. A rectangularly-shaped chute is secured to the cross frame 18 and its oblong open upper end is located directly beneath the point of closest proximity of the rolls l1 and 21.

A vibratory feeder 8 l having a hopper 82, is located above each of the rolls l1 and 21. The vibratory feeders are each mounted on a cross frame 83 which extends across between the bearing blocks l4 and IE or 24 and 24. The troughs 84 of the feeders 8| are approximately two-thirds as wide as the main portions of the rolls i1 and 21 and their open ends extend close to the fixed auxiliary leveling rolls 56 and 10.

Operation their surfaces of closest proximity move toward each other and downward at the same peripheral speed. The auxiliary rolls 5' and 59, or 14 and 1|, turn in directions opposite to the main roll with which they are associated.

Pressure is built up in the hydraulic cylinders 31, which forces the movable bearing blocks 24 and 26 toward the stationary blocks l4 and It. The main rolls l1 and 21 are kept from engagement by the spacers 29 and 24.

Heating fluid is introduced into the interiors of the rolls l1 and 21. The vibratory feeders ll feed powdered material into the spaces between the leveling rolls 5. and I0 and the main rolls l1 and 21. This material is smoothed into an even layer by the action of the leveling rolls 5' Y up to a point at which it permits the main rolls to be forced apart only a slight amount by the material being squeezed between them and exerts tremendous pressure on such material. The two layers being carried by the two, main rolls are thus merged into one which is greatly densified and compacted.

The temperature of the heating fluid which is introduced into the interior of the main rolls l1 and 21 varies according to the type of fusible molding powder which is being compacted. The temperature should be high enough to bring the powder to a plastic state by the time it passes between the main rolls. The auxiliary rolls 56, 59, I and H are all cooled to prevent any of the material from sticking to their surfaces. Because of their proximity to the main rolls, they tend to assume the temperature of the main rolls unless they are cooled. The knives 15 are for the purpose of cleaning off the rolls any particles of material which may break away from the main strip of compacted material leaving the pressure rolls, particularly at the edges of thestrip. The compacted material enters the chute 80 which leads to a cooled granulating machine where it is cut into granules of the desired size.

The device can be operated satisfactorily in some cases by using only one auxiliary roll, preferably the fixed roll 56 or above each main roll, and omitting the other auxiliary roll from each main rolL However, for most fusible powders, it has been found desirable to employ all of the auxiliary rolls illustrated in' Fig. IV in order to cause the heat from the main rolls to fuse all of the material and thus drive out all of the air and other'gas and produce a uniformly dense sheet. In any case the main rolls should be substantially horizontal and are preferably driven at substantially the same peripheral speed.

The powdered material may be fed to only one of the main rolls if desired.

By forming the material into a relatively dense, compact layer on each of the main rolls l1 and 21, the auxiliary rolls cause the material to be heated rapidly to the temperature of the main rolls before it passes between the main rolls. The material in its initial fluffy powdered form is a very poor conductor of heat, and it would not be heated satisfactorily by contact with the main rolls if it were not compressed on the main rolls by the auxiliary rolls.

rial is carried forward with the surface of the pressure roll, a fixed auxiliary roll located ahead of such point for forming said material into a uniform layer on the pressure roll, and an auxiliary 1 pressure roll ahead of said fixed auxiliary roll for preliminarily compressing said layer, the.

layer of material being pre-heated as it is carried along by the rotation of the pressure roll, and, being fused and densified as it passes between the pressure rolls.

2. An apparatus for preheating and densifying a fusible powdered material comprising in combination, a pair of substantially horizontal pressure rolls, each having an internal passage supplied with a heating medium, means for rotating the-pressure rolls in opposite directions, powderfeeding means for feeding said material to one of the pressure rolls at a point at which said material is carried forward with the surface of the pressure roll, a fixed auxiliary lOil having an internal passage supplied with a cooling medium,

Various embodiments of'the invention may be devised to meet various requirements.

Having described the invention, we claim:

1. An apparatus for preheating and densifying a fusible powdered material comprising, in combination, a pair of substantially horizontal pressure rolls, each having an internal passage supplied with a heating medium, means for rotating the pressure rolls in opposite directions, powderfeeding means for feeding said material to one of the pressure rolls at a point at which said matclocated ahead of such point for forming said material into a uniform layer on the pressure roll, and a floating auxiliary roll having an internal passage supplied with a cooling medium, located ahead of said fixed auxiliary roll for preliminarily compressing said layer by its ownweight, the layer of material being pre-heated as it is carried along by the rotation of the pressure roll, and being fused and densified as it passes between the pressure rolls.

3. An apparatus for preheating and densifying a fusible powdered material comprising, in combination, a pair of substantially horizontal pressure rolls, each having an internal passage supplied with a heating medium, means for rotating the pressure rolls downward toward one anotherat substantially the same peripheral speed, powder-feeding means for feeding said material at a point adjacent the top of each of said pressure rolls, a fixed auxiliary roll located ahead of each of such pointsfor forming said material into a uniform layer on each pressure roll, and an auxiliary pressure roll ahead of each of said fixed auxiliary rolls for preliminarily compressing each layer, each of the layers of material being preheated as it is carried along by the rotation of the pressure roll, and the two layers being fused and compacted into a single layer as they pass between the pressure rolls.

4. An apparatus for preheating and densifying a fusible powdered material comprising, in combination, a pair of substantially horizontal pressure rolls, each having an internal passage supplied with a heating medium, means for rotating the pressure rolls downward toward one another at substantially the same peripheral speed, means for feeding said material at a point adjacent the top of each of said pressure rolls, a fixed auxiliary roll having an internal passage supplied with a cooling medium, located ahead of each of such points for forming said material into a uniform layer on each pressure roll, an auxiliary pressure roll having an internal passage supplied with a 

